Published
Edited
Jan 19, 2021
chart = {
const svg = d3.create("svg")
.attr("viewBox", [0, 0, width, height]);
svg.append("g")
.call(xAxis);
svg.append("g")
.call(yAxis);
svg.append("path")
.datum(data)
.attr("fill", "none")
.attr("stroke", "steelblue")
.attr("stroke-width", 1.5)
.attr("stroke-linejoin", "round")
.attr("stroke-linecap", "round")
.attr("d", line);
svg.append("g")
.attr("class","references")
.attr("id",`references-group-App`);
svg.append("rect")
.attr("id",`rect-overlay-App`)
.attr("class","rect-overlay")
.attr("fill","none")
.style("pointer-events","all")
.attr("x",0)
.attr("y",0)
.attr("width",width)
.attr("height",height)
.on("mouseover",function() {mouseOver(this);})
.on("mousemove",function() {mouseOver(this);})
.on("mouseout",function() {mouseOut(this);})
return svg.node();
}
timer = () => {}
timer
function mouseOver(el) {
let mouseEvent = d3.mouse(el);
let x0 = x.invert(mouseEvent[0]);
let xLevel = +d3.timeDay(x0)
let selectedData = null
const myReduce = (list, initialValue, reducer) => {
if(list.length === 0) {
return initialValue;
} else {
const [first, ...rest] = list;
const updatedAcc = reducer(initialValue, first);
const timer = setTimeout(function(){
return myReduce(rest, updatedAcc, reducer);
}, 500)
if(list.length === 0) clearTimeout(timer);
}
}
d3.select(`#references-group-App`)
.append("line")
.attr("x1",x(xLevel))
.attr("y1",0)
.attr("x2",x(xLevel))
.attr("y2",100)
.attr('stroke', 'black')
if(data && data.length > 0){
selectedData = myReduce(data, data[0], (a,b) => {
d3.select(`#references-group-App`)
.append("line")
.attr("x1",x(a["date"]))
.attr("y1",0)
.attr("x2",x(a["date"]))
.attr("y2",100)
.attr('stroke', 'red')
.attr('opacity', 0.1)
d3.select(`#references-group-App`)
.append("text")
.attr("x",x(a["date"]))
.attr("y",100)
.html(a["date"])
.attr('font-size', '8px')
.attr('opacity', 1)
.transition().duration(300)
.attr('opacity', 0)
d3.select(`#references-group-App`)
.append("line")
.attr("x1",x(b["date"]))
.attr("y1",0)
.attr("x2",x(b["date"]))
.attr("y2",100)
.attr('stroke', 'blue')
.attr('opacity', 0.1)
d3.select(`#references-group-App`)
.append("text")
.attr("x",x(b["date"]))
.attr("y",10)
.html(b["date"])
.attr('font-size', '10px')
.attr('opacity', 1)
.transition().duration(300)
.attr('opacity', 0)
return Math.abs(b['date'] - xLevel) <= Math.abs(a["date"] - xLevel) ? b :a
})
}
if(selectedData){
let xPos = x(selectedData['date'])
let yPos = y(selectedData['value'])
console.log(xPos, yPos)
}
}
function mouseOut(){
d3.select(`#references-group-App`).selectAll('line').remove()
clearTimeout(timer)
}
data = Object.assign((d3.csvParse(await FileAttachment("aapl.csv").text(), d3.autoType)).map(({date, close}) => ({date, value: close})), {y: "$ Close"}).slice(0,100)
line = d3.line()
.defined(d => !isNaN(d.value))
.x(d => x(d.date))
.y(d => y(d.value))
x = d3.scaleUtc()
.domain(d3.extent(data, d => d.date))
.range([margin.left, width - margin.right])
y = d3.scaleLinear()
.domain([0, d3.max(data, d => d.value)]).nice()
.range([height - margin.bottom, margin.top])
xAxis = g => g
.attr("transform", `translate(0,${height - margin.bottom})`)
.call(d3.axisBottom(x).ticks(width / 80).tickSizeOuter(0))
yAxis = g => g
.attr("transform", `translate(${margin.left},0)`)
.call(d3.axisLeft(y))
.call(g => g.select(".domain").remove())
.call(g => g.select(".tick:last-of-type text").clone()
.attr("x", 3)
.attr("text-anchor", "start")
.attr("font-weight", "bold")
.text(data.y))
function sleep(milliseconds){
return new Promise(resolve => setTimeout(resolve, milliseconds))
}
margin = ({top: 20, right: 30, bottom: 30, left: 40})
height = 500
d3 = require("d3@5")
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